Disk grinder.



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DISK GRINDER. v

' APPLICATION FILED SEPT.21.1911. 115mm. Patented 0015,1915.

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FREDERICK, N. GARDNER AND FREDERIC E. GARDNER, 0F BELOIT, WISCONSIN, ASSIGNORS 0F ONE-THIRD T0 LOUIS WALDO THOMPSON, 0F BELOIT, WISCONSIN; ALICE M. GARDNER EXECUTRIX OF SAID FREDERICK N. GARDNER, DECEASED.

DISK GRINDER.

Application filed September 21, 1911.

To all whom it mayconcern:

Be it known that we, FREDERICK N. GARD- NER and Fnnntnro E. GARDNER, citizens of the United States, residing at Beloit, in the county of Rock and State of \Visconsin, have invented certain new and useful Improvements in Disk Grinders, of which the following is a specification.

This invention relates to the particular class of grinding machines known as disk grinders. Such machines comprise a rotary wheel which 'is fixed on the extreme end of a spindle and is provided with a removable abrading surface 'on its unobw,

structed side or face opposite to the body of said spindle. Heretofore the abrading surface has been formed by means of a disk of cloth or paper covered upon one side with a layer of abrasive grains, the other side of said disk being cemented to the rotatory wheel of the grinding machine. In attaching the disk to the rotatory wheel it is necessary to use some kind of press for pressing the disk closely and uniformly to the wheel. When the abrading surface is worn off, the disk and the cement must be removed from the wheel before another disk can be applied, such removal requiring the use of hot water andscrapmg and scrubbing of the wheel with caustic detergents. The cloth or paper backing of the wornout disk is discarded. I

The necessity of cementing and pressing the disk to the wheel has seriously limited the field of usefulness of disk grinders, because the press costs nearly as much as the grinder, the who :1 must remain in the press for several hours, and therefaced wheel should be permitted to dry for two or three hours after removal from the press, the grinder meanwhile being out of commission unless an extra supply of wheels has been provided.

The objects of our invention are to eliminate the waste of material incident to the use of paper or cloth-backed disks, to save the expense of-thecement, to reduce to a minlmum the time, labor and investment 1nvolved in refacing the rotatory wheel, and to obtain greater grinding efficiency. These objects we attain by providing a metallicwheel comprising two fiat plate-like sec tions divided on a plane extending perpendicularly to the axis of thewheel or par- Specification of Letters Patent.

"The wheel sections 3 and Patented (Dot. 5, 1915.

Serial No. 650,649.

allel to the side faces of said sections. One section is rigidly fixed to the extreme end of the rotary spindle of the machine, and the other section is approximately co-extensive with the first and comprises a thin disk or plate presenting a continuous or unbroken forward side having a layer of abrading grains cemented directly to and covering said forward side, said wheel sections being detachably secured together face to face. 1 V

In the accompanying drawings, Figure 1 is a vertical central section through the rotatory wheel of a disk grinder embodying the features of our invention, a portion of the spindle being also shown. Fig. 2 is a sectional view taken in the plane of dotted line 2 2 of Fig. 1, and upon a smaller scale. In the drawing, 1 indicates the spindle and 2 the improved rotatory disk wheel, said wheel comprising a portion or plate 3 which is attached to the spindle by means of the collar l and screws 5. Said wheel further comprises the thin disk or plate 6 provided upon one side with a layer of abrasive grains 7 cemented directly to said plate. 6 are detachably secured together by any suitable means,

preferably screw-threaded means to provide returned to the manufacturer to be refaced,

and another section 6 having a new abrading surface is secured to the wheel-section 3. 'It. will be apparent that our invention obviates the expense and annoyance of using cement to attach the abrading surface to i the rotatory wheel, that the waste of material incident to the use of cloth or paper-backed disks is obviated, and that a worn abrading surface may be expeditiously and conveniently replaced. Moreover, the abrasive grains, being cemented directly to metal, have much more cutting efficiency than when mounted upon elastic and springy material such as cloth or paper, since when the abradinggrains are attached directly to the metal they are positively and rigidly held'up to the material being ground.

-We claim as our invention:

In a disk grinder, the combination of a rotary spindle, a grinding wheel mounted thereon consisting of two flat plate-like sections divided on a plane extending perpendicularly to the aXis of said spindle and wheel, one of said sections being a circular metallic rear plate which is rigidly fixed on the extreme end of said spindle, the other section being a thin circular disk positioned face to face and co-extensive with said rear plate, said disk having a layer of abrasive material cemented to and covering its unobstructed forward face, said face being plane and unrecessed and the disk and abrasive thereon presenting a continuous or unbroken fiat abrading surface at all points 15 within its circumference, and a plurality of devices for clamping said disk to the face of said rear plate, said devices lying behind the plane of said layer of abrasive material.

In testimony'whereof We aflix our signa- 2O tures in the presence of two witnesses. FREDERICK N. GARDNER. FREDERIC E. GARDNER.

Witnesses:

H. U. ADAMS, CLARA BAUKIN. 

